HEADSUP: HZ=1000 by default on i386
phk at phk.freebsd.dk
Thu Nov 4 08:36:54 PST 2004
In message <418A5A72.6020700 at freebsd.org>, Scott Long writes:
>>> 2) 1000 is not a good choice, because we can't approximate it well
>>> with the 8254. 1268 is better, 1381 is even better, 1903 is the
>>> best we can do between 1000 and 2000, 2299 is the best we can do
>>> between 1000 and 5000.
>> I played with it here and found that 1000 actually works better than 941.
>> (1193182 / 941 ~= 1268) because the 941 gives a slow beat against 1Hz.
>> It is actually preferable to have a fast beat (jitter) than a slow
>> beat (wander), particularly for people doing benchmarks.
>What timing hardware is used on amd64? Would it suffer there too?
I only tested on i386, but any platform would suffer from this kind
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